Method, device, and system for disinfection

ABSTRACT

Embodiments of the invention relate generally to disinfection and, more particularly, to methods, devices, and systems for disinfection of a space. In one embodiment, the invention provides a disinfecting system comprising: a disinfecting composition; and a device for producing a fog of the disinfecting composition, the fog comprising liquid droplets having diameters between about 0.5 micron and about 20 microns. In some embodiments, the invention includes a dehumidifying device for removing the fog of the disinfecting composition from the space.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of co-pending U.S. patentapplication Ser. No. 16/231,480, filed 22 Dec. 2018, which claims thebenefit of U.S. patent application Ser. No. 15/108,745, filed 28 Jun.2016, now U.S. Pat. No. 10,188,764, which is the U.S. national phase ofPCT Patent Application Serial No. PCT/US2015/010447, filed 7 Jan. 2015,which in turn claims priority to then-pending U.S. Provisional PatentApplication Ser. No. 61/924,980, filed 8 Jan. 2014, each of which ishereby incorporated herein.

BACKGROUND

Embodiments of the invention relate generally to disinfection and, moreparticularly, to methods, devices, and systems for disinfection of anenclosed space.

Infectious agents, including fungi, bacteria, and viruses, may be foundin many areas frequented or inhabited by humans and animals. Within suchareas, such infections agents may be transmitted to humans and animalsthrough contact with the area's surfaces and/or inhalation of airborneagents within the area's atmosphere. Such areas include, withoutlimitation, classrooms, gymnasiums and locker rooms, airplane cabins,cruise ships, veterinary clinics, hospitals, including hospitaloperating rooms, nursing homes, daycare centers, public restrooms,subway cars, and train cars.

An effective method of disinfecting both the atmosphere and thesurfaces—horizontal, vertical, and obscured—within such spaces maysignificantly reduce the instances of infection by these agents.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of this invention will be more readilyunderstood from the following detailed description of the variousaspects of the invention taken in conjunction with the accompanyingdrawings that depict various embodiments of the invention, in which:

FIG. 1 shows a disinfecting apparatus according to one embodiment of theinvention.

It is noted that the drawings of the invention are not to scale. Thedrawings are intended to depict only typical aspects of the invention,and therefore should not be considered as limiting the scope of theinvention.

SUMMARY OF EMBODIMENTS OF THE INVENTION

In one embodiment, the invention provides a method of disinfecting anarea or enclosed space, the method comprising: introducing into the areaor enclosed space a fog of a disinfecting composition comprising liquiddroplets having diameters between about 0.5 micron and about 20 micron,the disinfecting composition comprising at least one of the following:hypochlorous acid, hypochlorite ion, sodium hypochlorite, chlorine,silver, hydrogen peroxide, ethaneperoxoic acid,tetraacetylethylenediamine, caprylic acid, alkyl dimethyl benzylammonium chloride, didecyl dimethyl ammonium chloride, triethyleneglycol, peroxyacetic acid, isopropyl alcohol, octanaminium, octyl decyldimethyl ammonium chloride, benzyl-p-chlorophenol, phenylphenol,dimethyl benzyl ammonium saccharinate, sodium dichloroisocyanuratedehydrate, or sodium chlorite.

In another embodiment, the invention provides an apparatus fordisinfecting an area or enclosed space, the apparatus comprising: adevice for producing a fog comprising liquid droplets having diametersbetween about 0.5 micron and about 20 microns; and

at least one port for discharging the fog into the area or enclosedspace.

In still another embodiment, the invention provides a disinfectingsystem comprising: a disinfecting composition; and a device forproducing a fog of the disinfecting composition, the fog comprisingliquid droplets having diameters between about 0.5 micron and about 20microns.

In still yet another embodiment, the invention provides a dehumidifyingsystem comprising: a dehumidifying device including at least onemoisture filtering apparatus; and at least one additional moisturefiltering apparatus configured upstream of the dehumidifying device. Insome embodiments of the invention, the at least one moisture filteringapparatus, the at least one additional moisture filtering apparatus, orboth, may include or comprise a low-moisture droplet mesh screen.

DETAILED DESCRIPTION

Methods according to various embodiments of the invention include theuse of a high-density fogging delivery system to produce a high-densityfog of a disinfecting composition which is then distributed within anarea, such as an enclosed space, to provide disinfection of infectionsagents. The disinfecting composition, according to some embodiments ofthe invention, includes hypochlorous acid and hypochlorite ion. In otherembodiments of the invention, the disinfecting composition includes oneor more of sodium hypochlorite, chlorine, silver, or hydrogen peroxide.In still other embodiments, the disinfecting composition mayadditionally or instead include one or more of ethaneperoxoic acid,tetraacetylethylenediamine, caprylic acid, alkyl dimethyl benzylammonium chloride, didecyl dimethyl ammonium chloride, triethyleneglycol, peroxyacetic acid, isopropyl alcohol, octanaminium, octyl decyldimethyl ammonium chloride, benzyl-p-chlorophenol, phenylphenol,dimethyl benzyl ammonium saccharinate, sodium dichloroisocyanuratedehydrate, or sodium chlorite. The disinfecting composition may beprovided as a pre-manufactured liquid or prepared from separatecomponents within the delivery system itself.

Disinfecting compositions such as hypochlorous acid and hypochlorite ionhave been found to be highly effective against virtually all fungi,bacteria, and viruses while also showing no adverse effect on thecornea, sclera, mucous membrane, oropharynx/uvula area, epidermis,dermis, or fatty tissues of humans or animals after extended contact.

For example, a high-density fogging delivery system according to oneembodiment of the invention may include a piezo ultrasonic discnebulizer or similar device capable of producing a fog of thedisinfecting composition comprising liquid droplets between about 0.5micron and 20 microns in diameter, e.g., between about 0.5 micron andabout 3 microns in diameter.

Such nebulizers typically function from a fixed position in the base ofa storage tank or receptacle, where a vibrational energy—generated froma supplied voltage—is transmitted in a direction perpendicular to theresonant surface of the piezo resonator.

It has been discovered that the distance between the surface of thepiezo resonator and the surface of the liquid in the storage tank has amajor effect on atomization efficiency. Thus, according to someembodiments of the invention, the piezo nebulizer or similar device isdisposed in an atomizing tray, where the depth of the disinfectingcomposition—and therefore the distance between the piezo resonator andthe surface of the disinfecting composition—may be substantiallymaintained through use, for example, of a recirculating pump or similarapparatus even as the disinfecting composition is atomized anddischarged.

It has also been found that the frequency of oscillation of the piezoresonator has a significant effect on the efficiency of disinfectionusing systems and devices according to the invention. Frequenciesbetween about 1.50 MHz and about 2.50 MHz, and even more preferablybetween about 1.65 MHz and about 2.10 MHz, produce a fog of dropletshaving optimal diameters for efficient dispersal without saturating thearea to be disinfected. Lower frequencies produce droplets that are toolarge and which “drop out” of the air stream. Higher frequencies producedroplets that are too small and which tend to “float” or remainsuspended in the air stream without contacting the surfaces sought to bedisinfected.

One skilled in the art will recognized that fogs of disinfectingcompositions may be produced by other methods as well. Such methodsinclude, for example, small orifice misting nozzles, which pass a fluidthrough a small orifice at high velocity, where the resulting shearingforces break the fluid into fine droplets.

Impingement misting nozzles may also be employed. These devices forcethe fluid onto a pin or similar structure just outside the exit orifice,which again breaks the fluid into very fine droplets. These nozzles mayemploy a larger orifice, as compared to those in the small orificemisting nozzles, which may be beneficial when utilizing disinfectingcompositions with higher viscosities and/or suspensions.

Air atomizing nozzles may also be employed in embodiments of theinvention. These pneumatic nozzles use compressed air to break apart thefluid, allowing for very fine atomization, even at low pressures.

Once produced, regardless of the method, a fog of disinfectantcomposition may be discharged from the delivery system through one ormore ports or tubes using a fan. The fog may then be permitted to expandthroughout the area or enclosed space, thereby disinfecting both itsatmosphere and its surfaces, including obscured or recessed surfacesthat would otherwise be difficult or impossible to disinfect.

Fogs of a disinfecting composition having different particle sizes maybe produced using other fogging devices. For example, using a single ormulti-head spray nozzle, a disinfecting fog having droplets betweenabout 3 microns and about 20 microns, e.g., between about 3 microns andabout 5 microns, may be produced. Using a single or multi-headhigh-speed rotary disc nebulizer will produce a fog having dropletsbetween about 2 microns and about 20 microns, e.g., between about 2microns and about 5 microns.

Employing disinfecting fogs comprised of liquid droplets in size rangessuch as these provide at least two clear advantages over otherdisinfecting methods and systems. First, the small droplet size permitsthe disinfecting fog to reach into small recesses, including minutecracks or grains in surfaces that otherwise cannot be reached. Second,the small droplet size improves the extent of disinfection, regardlessof the size of the infectious agent. For example, disinfecting fogscomprising droplets of this size have been shown to kill virtually allfungi, bacteria, and viruses, including methicillin-resistantStaphylococcus aureus (MRSA) and Clostridium difficile.

The pH of the disinfecting composition is also important in achievingeffective disinfection. Disinfecting compositions having a pH betweenabout 3 and about 7.5, e.g., between about 5 and about 7.5, e.g.,between about 5 and about 7, e.g., between about 6 and about 7, havebeen found to be particularly effective.

In still other embodiments of the invention, an electrical charge may beinduced in or imparted to the disinfecting fog. For example, anelectrostatic aerosol applicator may be employed to produce a negativelycharged disinfecting fog by passing the fog across or adjacent aninduction electrode, which induces a charge in each droplet. Positivelycharged surfaces in the area or enclosed space will attract thenegatively charged droplets, causing the droplets to adhere, even, forexample, on downwardly-facing horizontal surfaces, which otherwise wouldbe less likely than upwardly-facing horizontal surfaces to come incontact with uncharged droplets. In fact, it has been found that theelectrical attraction of such negatively-charged droplets isapproximately 40 times stronger than is the force of gravity on suchdroplets.

In addition, the induction of a charge on the droplets of thedisinfecting fog reduces the rate and extent of agglomeration among thedroplets. This has the effect of improving distribution of thedisinfecting fog within the area or enclosed space.

In still other embodiments of the invention, a disinfecting system mayinclude a moisture-eliminating device or apparatus. This provides anumber of advantages, including the reduction of moisture whichotherwise may harbor or promote the growth of molds.

For example, after distributing a disinfecting fog within an area orenclosed space, a low-micron moisture droplet filter or a low-micronmoisture droplet air-flow vane may be used to remove up to about 99% ofthe volume of disinfecting composition initially introduced to the areaor enclosed space. In doing so, the filter traps both the disinfectingcomposition and any infectious agents on its surfaces, thereby providinga secondary field for disinfection. Dehumidifying the atmosphere of thearea or enclosed space prior to introduction of the disinfecting fog hasalso been found to improve the disinfecting capabilities of the methods,devices, and systems of the invention.

Some embodiments of the invention employ an in-line dehumidifier, i.e.,a dehumidifier incorporated into the same device that introduces thedisinfecting composition into the area or enclosed space. An in-linedehumidifier has been found to more quickly and efficiently remove thedisinfecting composition than can an external dehumidifier of the sameor larger dehumidifying capacity.

For example, a disinfecting device according to one embodiment of theinvention that does not include a dehumidifying device was employed todisperse a total of 2.5 L of a disinfecting solution into a sealed spaceat a rate of 180-200 mL per minute. The sealed space was fogged to“white out” in 14 minutes. An external dehumidifying unit (a PhoenixR200 LGR dehumidifier) was then used in conjunction with four externalcirculating fans to clear the room in 22 minutes.

A device according to another embodiment of the invention that includedan in-line dehumidifying device was employed to disperse 2.5 L of thesame disinfecting solution into a sealed space of the same size at thesame rate of 180-200 mL per minute. Once fogged to “white out” in thesame 14 minutes, the in-line dehumidifying device was employed andcleared the room in seven minutes, a 48% improvement over the use of theexternal dehumidifier and circulating fans.

More specifically, the in-line dehumidifier was outfitted with alow-micron moisture droplet mesh screen upstream of the dehumidifier andanother within the dehumidifier itself. The upstream “pre-dehumidifier”screen was able to remove 500 mL of liquid ahead of the dehumidifier,with the dehumidifier itself then removing another 1000 mL. Thisupstream dehumidification allowed for more efficient functioning of thedehumidifier, permitting faster clearing of the room.

Such low-moisture droplet mesh screens capture larger (about 3 microndiameter and larger) droplets differently than smaller (less than about3 micron diameter) droplets. The larger droplets have sufficientmomentum to “break” from the air stream in which they are carried andinertia will carry them in a straight line if the air stream turns, sothat these larger droplets carry on and impact a filter surface. Theselarger droplets are collected more efficiently at higher velocities.

The smaller droplets typically do not have sufficient mass to “break”from the air stream and are instead captured by filter fibers by directcontact.

Very small (submicron) droplets, on the other hand, while also nothaving sufficient momentum to break from the air stream, exhibit random(Brownian) movement within the air stream. Such very small droplets arealso collected by direct contact with filter fibers and are retained bysuch fibers by van der Waals forces. However, these very small dropletsare more efficiently collected at lower air stream velocities, whichincreases the likelihood that a very small droplet will contact a filterfiber, even where the space between the fibers is greater than thediameters of the droplets.

Accordingly, a dehumidification system according to embodiments of theinvention that includes a plurality of air flow velocities, as may beachieved, for example, by altering the volume through which the airstream flows, may be more effective in removing both larger and verysmall droplets than would a system that substantially maintains a singleair flow velocity.

In other embodiments of the invention, dehumidifying devices accordingto the invention may include filters having low-micron moisture dropletair-flow vanes. These filters may include those that employ animpingement-type separator. These have curved passages through which thehumidified air passes. The mass of the disinfectant droplets beinggreater than that of the air in which they are contained results intheir impact with the surfaces of the curved passages. These droplets,after impacting the passage surfaces, form a liquid film that coalescesinto larger droplets that are gravitationally discharged from thefilter. As such, according to some embodiments of the invention, acondensation tank or similar device may be provided for storage ofliquids accumulated as a consequence of the dehumidification process.

In some embodiments of the invention, dehumidification of the atmosphereof an area or enclosed space is achieved through the intake ofnon-dehumidified air through multiple intakes of a disinfecting deviceand/or the discharge of dehumidified air through multiple other ports ofthe device. Having multiple intake and discharge points creates airturbulence in the area or enclosed space, further enhancing thedehumidifying process.

In still other embodiments of the invention, a carbon filter or similardevice may be employed to capture any chlorine or chloride gas during orseparate from such dehumidification, which may serve to reduce oreliminate undesirable odors from the dehumidified air. A gram ofactivated carbon may have a surface area between 500 m² and 1500 m², anda pound of activated carbon will adsorb about one sixth of its weight inchlorine compounds alone, while also removing volatile organic compounds(VOCs), etc.

FIG. 1 shows a perspective view of an apparatus 100 according to oneembodiment of the invention. Apparatus 100 includes a tank 10 forcontaining a disinfecting composition. Tank 10 includes a base 12 towhich one or more nebulizers or similar devices (not shown) may beaffixed or secured.

Once a fog of disinfecting composition is produced, such as describedabove, the fog may be discharged through one or more ports or tubes 20,which, as shown in FIG. 1 may be angled with respect to vertical and/orhorizontal axes of apparatus 100. Such discharge may be achieved using,for example, a fan or similar device (not shown).

Apparatus 100 further includes a dehumidifying device 30 having adehumidifier fan 32 and a dehumidifier compressor 34, as well as afiltering device 40, such as an activated carbon filter. As noted above,apparatus 100 may further include one or more moisture dropleteliminator filters 36 or similar devices, which may be disposed toreceive incoming air upstream of the dehumidifying device.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the disclosure.As used herein, the singular forms “a,” “an,” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof.

This written description uses examples to disclose the invention,including the best mode, and also to enable any person skilled in theart to practice the invention, including making and using any devices orsystems and performing any related or incorporated methods. Thepatentable scope of the invention is defined by the claims, and mayinclude other examples that occur to those skilled in the art. Suchother examples are intended to be within the scope of the claims if theyhave structural elements that do not differ from the literal language ofthe claims, or if they include equivalent structural elements withinsubstantial differences from the literal language of the claims.

What is claimed is:
 1. An apparatus for disinfecting an area or enclosedspace, the apparatus comprising: an atomizing tray; an atomizing devicewithin the atomizing tray, the atomizing device being operable toproduce a fog comprising liquid droplets having diameters between about0.5 micron and about 20 microns; a tank for holding a quantity of adisinfecting composition; a recirculating pump for transferring thedisinfecting composition from the tank to the atomizing tray andmaintaining a depth of the disinfecting composition within the atomizingtray; at least one port for discharging the fog into the area orenclosed space; and an in-line dehumidifying device.
 2. The apparatus ofclaim 1, wherein the atomizing device for producing the fog includes apiezo disc nebulizer operable at a frequency between about 1.50 MHz andabout 2.50 MHz.
 3. The apparatus of claim 1, wherein the atomizingdevice for producing the fog includes a high-speed rotary disc atomizer.4. The apparatus of claim 1, wherein the atomizing device for producingthe fog includes at least one device selected from a group consistingof: small orifice misting nozzles, impingement misting nozzles, and airatomizing nozzles.
 5. The apparatus of claim 1, further comprising: adevice for inducing an electrical charge in at least a portion of theliquid droplets.
 6. The apparatus of claim 1, further comprising: afiltering device for removing odor from an atmosphere.
 7. The apparatusof claim 6, wherein the filtering device includes activated carbon.
 8. Adisinfecting system comprising: a tank containing a quantity of adisinfecting composition; and an atomizing tray; a recirculating pumpfor transferring the disinfecting composition from the tank to theatomizing tray and maintaining a depth of the disinfecting compositionwithin the atomizing tray; an atomizing device within the atomizingtray, the atomizing device being operable to produce a fog of thedisinfecting composition, the fog comprising liquid droplets havingdiameters between about 0.5 micron and about 20 microns, and the devicecomprising: a high-speed rotary disc atomizer; at least one port fordischarging the fog into the area or enclosed space; and an in-linedehumidifying device.
 9. The disinfecting system of claim 8, wherein thedisinfecting composition includes at least one of the following:hypochlorous acid, hypochlorite ion, sodium hypochlorite, chlorine,silver, hydrogen peroxide, ethaneperoxoic acid,tetraacetylethylenediamine, caprylic acid, alkyl dimethyl benzylammonium chloride, didecyl dimethyl ammonium chloride, triethyleneglycol, peroxyacetic acid, isopropyl alcohol, octanaminium, octyl decyldimethyl ammonium chloride, benzyl-p-chlorophenol, phenylphenol,dimethyl benzyl ammonium saccharinate, sodium dichloroisocyanuratedehydrate, or sodium chlorite.
 10. The disinfecting system of claim 8,wherein the disinfecting composition comprises hypochlorous acid andhypochlorite ion.
 11. The disinfecting system of claim 8, wherein thedisinfecting composition comprises hydrogen peroxide and peroxyaceticacid.
 12. The disinfecting system of claim 8, wherein the atomizingdevice for producing the fog includes a piezo disc nebulizer operable ata frequency between about 1.50 MHz and about 2.50 MHz.
 13. Thedisinfecting system of claim 8, further comprising: a device forinducing an electrical charge in at least a portion of the liquiddroplets.
 14. A disinfecting apparatus comprising: at least one rotarydisc atomizer; and a port for discharging an atomized disinfectingcomposition.
 15. The disinfecting apparatus of claim 14, wherein the atleast one rotary disc atomizer is operable to produce droplets ofdisinfecting composition having a diameter between about 2 microns andabout 20 microns.
 16. The disinfecting apparatus of claim 15, whereinthe at least one rotary disc atomizer is operable to produce droplets ofdisinfecting composition having a diameter between about 2 microns andabout 5 microns.
 17. The disinfecting apparatus of claim 14, wherein theat least one rotary disc atomizer includes a multi-head high-speedrotary disc nebulizer operable to produce droplets of disinfectingcomposition having a diameter between about 2 microns and about 20microns.
 18. The disinfecting apparatus of claim 14, further comprising:a dehumidifying device; and at least one filter having low-micronmoisture droplet air-flow vanes.
 19. The disinfecting apparatus of claim18, wherein the at least one filter includes an impingement-typeseparator.
 20. The disinfecting apparatus of claim 15, furthercomprising: a tank for containing the disinfecting composition.